From d853a40f90798b307a30824f01978a80580e2762 Mon Sep 17 00:00:00 2001
From: Reece Williams <reecepbcups@gmail.com>
Date: Sat, 25 May 2024 10:43:06 -0500
Subject: [PATCH] impl BurnHeldBalance msgServer with test

---
 app/app.go                           |  2 +-
 x/manifest/keeper/msg_server.go      | 15 ++++++
 x/manifest/keeper/msg_server_test.go | 74 ++++++++++++++++++++++++++++
 3 files changed, 90 insertions(+), 1 deletion(-)

diff --git a/app/app.go b/app/app.go
index fbf1f7f..2d19fcc 100644
--- a/app/app.go
+++ b/app/app.go
@@ -204,7 +204,7 @@ var maccPerms = map[string][]string{
 	ibcfeetypes.ModuleName:       nil,
 	icatypes.ModuleName:          nil,
 	tokenfactorytypes.ModuleName: {authtypes.Minter, authtypes.Burner},
-	manifesttypes.ModuleName:     {authtypes.Minter},
+	manifesttypes.ModuleName:     {authtypes.Minter, authtypes.Burner},
 }
 
 var (
diff --git a/x/manifest/keeper/msg_server.go b/x/manifest/keeper/msg_server.go
index 9d6a38e..322e209 100644
--- a/x/manifest/keeper/msg_server.go
+++ b/x/manifest/keeper/msg_server.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 
+	sdk "github.com/cosmos/cosmos-sdk/types"
 	"github.com/liftedinit/manifest-ledger/x/manifest/types"
 )
 
@@ -47,3 +48,17 @@ func (ms msgServer) PayoutStakeholders(ctx context.Context, req *types.MsgPayout
 
 	return nil, ms.k.PayoutStakeholders(ctx, req.Payout)
 }
+
+// BurnHeldBalance implements types.MsgServer.
+func (ms msgServer) BurnHeldBalance(ctx context.Context, msg *types.MsgBurnHeldBalance) (*types.MsgBurnHeldBalanceResponse, error) {
+	addr, err := sdk.AccAddressFromBech32(msg.Sender)
+	if err != nil {
+		return nil, err
+	}
+
+	if err := ms.k.bankKeeper.SendCoinsFromAccountToModule(ctx, addr, types.ModuleName, msg.BurnCoins); err != nil {
+		return nil, fmt.Errorf("not enough balance to burn %s: %w", msg.BurnCoins, err)
+	}
+
+	return &types.MsgBurnHeldBalanceResponse{}, ms.k.bankKeeper.BurnCoins(ctx, types.ModuleName, msg.BurnCoins)
+}
diff --git a/x/manifest/keeper/msg_server_test.go b/x/manifest/keeper/msg_server_test.go
index 18fe7a9..4f4e270 100644
--- a/x/manifest/keeper/msg_server_test.go
+++ b/x/manifest/keeper/msg_server_test.go
@@ -235,3 +235,77 @@ func TestCalculatePayoutLogic(t *testing.T) {
 		}
 	}
 }
+
+func TestBurnCoins(t *testing.T) {
+	_, _, authority := testdata.KeyTestPubAddr()
+
+	f := initFixture(t)
+
+	k := f.App.ManifestKeeper
+	k.SetAuthority(authority.String())
+	ms := keeper.NewMsgServerImpl(k)
+
+	type tc struct {
+		name     string
+		initial  sdk.Coins
+		burn     sdk.Coins
+		expected sdk.Coins
+		success  bool
+	}
+
+	stake := sdk.NewCoin("stake", sdkmath.NewInt(100_000_000))
+	mfx := sdk.NewCoin("umfx", sdkmath.NewInt(100_000_000))
+
+	cases := []tc{
+		{
+			name:     "fail; not enough balance to burn",
+			initial:  sdk.NewCoins(),
+			burn:     sdk.NewCoins(sdk.NewCoin("stake", sdkmath.NewInt(7))),
+			expected: sdk.NewCoins(),
+		},
+		{
+			name:     "success; burn 1 token successfully",
+			initial:  sdk.NewCoins(stake, mfx),
+			burn:     sdk.NewCoins(sdk.NewCoin("stake", sdkmath.NewInt(7))),
+			expected: sdk.NewCoins(mfx, stake.SubAmount(sdkmath.NewInt(7))),
+			success:  true,
+		},
+		{
+			name:     "success; burn many tokens successfully",
+			initial:  sdk.NewCoins(stake, mfx),
+			burn:     sdk.NewCoins(sdk.NewCoin("umfx", sdkmath.NewInt(9)), sdk.NewCoin("stake", sdkmath.NewInt(7))),
+			expected: sdk.NewCoins(mfx.SubAmount(sdkmath.NewInt(9)), stake.SubAmount(sdkmath.NewInt(7))),
+			success:  true,
+		},
+	}
+
+	for _, c := range cases {
+		c := c
+		t.Run(c.name, func(t *testing.T) {
+			_, _, acc := testdata.KeyTestPubAddr()
+
+			// setup initial balances for the new account
+			if len(c.initial) > 0 {
+				require.NoError(t, f.App.BankKeeper.MintCoins(f.Ctx, "mint", c.initial))
+				require.NoError(t, f.App.BankKeeper.SendCoinsFromModuleToAccount(f.Ctx, "mint", acc, c.initial))
+			}
+
+			// validate initial balance
+			require.Equal(t, c.initial, f.App.BankKeeper.GetAllBalances(f.Ctx, acc))
+
+			// burn coins
+			_, err := ms.BurnHeldBalance(f.Ctx, &types.MsgBurnHeldBalance{
+				Sender:    acc.String(),
+				BurnCoins: c.burn,
+			})
+			if c.success {
+				require.NoError(t, err)
+			} else {
+				require.Error(t, err)
+			}
+
+			require.Equal(t, c.expected, f.App.BankKeeper.GetAllBalances(f.Ctx, acc))
+		})
+	}
+
+}